Large capacity mining draglines employ multiple dump blocks (or pulleys) to support and control the dragline bucket. For example, known mining draglines employ two dump blocks. The dump blocks are supported by a so-called “upper rigging” system. The configuration of the upper rigging system and the method in which the dump blocks are supported varies, even within mining-class dragline excavators.
Minimizing the mass of the upper rigging system permits a greater mass of overburden to be carried in the dragline bucket for a particular dragline structure. Furthermore, reducing the vertical dimension of the upper rigging system permits lifting of the bucket to a higher discharge position.
Because of the enormous forces and loads that a dragline bucket is subjected to and carries, the upper rigging system attempts to equalize the tension in each hoist rope, whilst still providing necessary degrees of freedom, so as to minimize component wear as the dragline operates in its intended manner.
The above references to the background art do not constitute an admission that such art forms a part of the common and/or general knowledge of a person of ordinary skill in the art. The above references are also not intended to limit the application of the spreader component disclosed herein.